Dynamics and Control of Atomic, Molecular and Macroscopic Systems

该研究项目将导致理解和控制量子系统的动力学，包括但不限于从原子中逃逸的电子，被困原子，超冷气体和分子。控制量子系统--电子、原子和分子--是现代物理学的“重大挑战”之一。这项研究跨越了物理、数学和化学的许多学科。微观量子系统可以通过理解和控制类似的宏观经典系统来理解和控制。经典力学中的新发现可以用来展示如何获得对量子系统的类似控制。 例如，混沌传输理论最初被引入研究在重力作用下相互作用的三体系统，最近被用于设计航天器轨道，检查彗星轨道，研究从火星到地球的流星运输，以及了解流体中的混合。 它将被用来研究原子从腔中逃逸，电子从高激发原子中逃逸，以及原子通过纳米结的传输。 这些系统只有几个自由度，粒子间的力是已知的和可控的，并且可以进行精确的测量。这项研究也与技术有关。电子从原子逃逸的机制类似于电子从纳米结（“设计者原子”）逃逸的机制，并且类似于光子从光学谐振器逃逸的机制。 此外，原子的高激发态可用作红外探测器，混沌电离过程已用于制作条纹相机。非线性动力学领域非常适合学生进行研究。一旦学生学习牛顿定律的基本方面，他们可以开始计算轨迹，并分析其结构。一个新的现象，在经典和量子可积系统称为monodromy将被研究。 此外，与将超冷原子从一个水库抽到另一个水库有关的新现象，“弹道原子泵”已经被发现，并将进一步探索。 预测未来观察到的“网球拍翻转”在孤立的分子的计算将进行。 最后，动态控制理论将应用于了解早产儿的呼吸。 例如，有人认为，当控制回路中的时间延迟使系统振荡时，会发生周期性呼吸暂停;这一理论将与弗吉尼亚大学提供的数据进行比较。

This research project will lead to understanding and control of the dynamics of quantum systems, including but not limited to electrons escaping from atoms, trapped atoms, ultracold gases, and molecules. Control of quantum systems -- electrons, atoms and molecules is one of the 'grand challenges' of modern physics. This research cuts across many disciplines in physics, mathematics and chemistry. Microscopic quantum systems can be understood and controlled by understanding and controlling the analogous macroscopic classical systems. New discoveries in classical mechanics can be used to show how to obtain similar control over quantum systems. For example, the theory of chaotic transport was first introduced to study systems of three bodies interacting under gravity, and has more recently been used to design spacecraft trajectories, examine orbits of comets, study transport of meteors from Mars to the Earth, and learn about mixing in fluids. It will be used to study escape of atoms from cavities, escape of electrons from highly excited atoms, and transport of atoms through nanojunctions. These are systems which have only a few degrees of freedom, for which the interparticle forces are known and controllable, and on which precise measurements can be made. This research is also connected to technology. The mechanisms of escape of electrons from atoms is similar to the mechanisms of escape of electrons from nanojunctions ('designer atoms') and similar to the mechanisms of escape of photons from optical resonators. In addition, highly excited states of atoms can be used as infrared detectors, and chaotic ionization processes have been used to make a streak camera. The field of nonlinear dynamics is excellent for introducing students to research. As soon as students learn elementary aspects of Newton's Laws, they can begin computing trajectories, and analyzing their structure.A new phenomenon in classical and quantum integrable systems called monodromy will be studied. Also new phenomena associated with pumping ultracold atoms from one reservoir to another, 'Ballistic Atom Pumps', has been discovered and will be further explored. Computations predicting future observations of the 'tennis-racket flip' in isolated molecules will be carried out. Finally dynamical control theory will be applied to understand respiration in premature infants. For example, it is believed that periodic apneas occur when time-delays in a control loop throw the system into oscillation; this theory will be compared with data provided by University of Virginia.